Welcome to WuJiGu Developer Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
1.0k views
in Technique[技术] by (71.8m points)

assembly - Conditional Compilation in assembler (.s) code for iPhone - how?

I have a few lines of assembler arm code in an .s file. Just a few routines i need to call. It works fine when building for the device, however when i switch to iPhone Simulator i get "no such instruction" errors. I tried to compile parts of the .s file conditionally with what i know:

#if !TARGET_IPHONE_SIMULATOR

But the assembler doesn't recognize these preprocessor directives (of course) and none of the conditional compilation techniques for assembler that i could remember or find worked, so i'm scratching my head now on how to avoid compilation of that assembler code when building for the Simulator. I also don't see a project option in Xcode that would allow me to compile the file or not depending on the target platform.

SOLVED:

All i was missing was the proper #import in the assembler file. I did not think of adding it because Xcode syntax highlighted any preprocessor directive in green (comment) which made me assume that these commands are not recognized when in fact they work just fine.

This works:

#import "TargetConditionals.h"

#if !TARGET_IPHONE_SIMULATOR

... asm code here ...

#endif
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

You do do it with a pre-processor macro. They are defined in TargetConditionals.h TARGET_IPHONE_SIMULATOR should be there! (You do need to #include it however.)


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to WuJiGu Developer Q&A Community for programmer and developer-Open, Learning and Share
...